Gas turbines, as well as certain other machines, are continuously being modified to provide increased efficiency and performance. These modifications include the ability to operate at higher temperatures and under harsher conditions, which may include the provision of cooling channels.
Increased cooling efficiency may be achieved by minimizing the distance between the cooling channels and the surface of the cooled article. Minimizing the distance between the cooling channels and the surface of the cooled article, however, necessarily yields a thin surface layer separating the cooling channels from the outside environment. For certain compositions and methods of formation, the thin surface layer may be susceptible to the formation of microcracks which may leak cooling fluid and lead to failure of the cooled article. By way of example, surface layer formed of hard-to-weld (HTW) alloys and surface layers formed by additive manufacturing techniques may have a particularly high susceptibility to the formation of microcracks.